Differential role of STIM1 in calcium handling in coronary and intrarenal arterial smooth muscles.

Calcium (Ca) dysregulation contributes to various vascular diseases, but the role and underlying mechanism of stromal interaction molecule-1 (STIM1) in Ca signaling and vasocontraction remain elusive. By using smooth muscle-specific STIM1 knockout (sm-STIM1 KO) mice and a multi myograph system, we investigated the differential role of STIM1 in Ca handling between coronary and intrarenal arterial smooth muscles. After STIM1 deletion, contractile responses to 5-HT were obviously reduced in coronary and intrarenal arteries in the sm-STIM1 KO mice, but not altered in U46619.